The "fertile ground" that allows moderates to become radicalized eventually boils down to polarization. It doesn't really matter whether the rhetoric is coming from Somalia, Nigeria, Mali, Turkey, Indonesia, Libya, Israel, Europe or the US; as long as the discourse goes in terms of "us vs them", many people will identify (and act) as victims.
But anyway, that wasn't the main point. The real point was to show that it wasn't a neocon that started our wars in Libya and Syria - it was today's iconic Progressive who did that, and without any sort of Congressional approval at all. Those wars can't be attributed to neocons, they are the Progressives' to own.
The group now calling itself "the Islamic State" was a comparatively minor Islamist group in Saddam's Iraq that hit the big time with the US invasion of Iraq and subsequent occupation, when it leveraged the disruption of that invasion and the currency of the al-Qaeda brand to rebrand itself as "al-Qaeda in Iraq" -- it was so successful -- seizing weapons and territory and becoming a substantial force that, particularly with the rest of the global al-Qaeda brand in decline, that it found it best to rebrand itself subsequently as "the Islamic State in Iraq".
Sure, when the Syrian Civil War escalated, it sent fighters there, who eventually remerged with ISI leading to its next rebrand as what is usually translated by official sources "the Islamic State in Iraq and the Levant" (but(alternatively translated as "the Islamic State in Iraq and Syria", which is where the "ISIS" label comes from), and the group later rebranded to simply "the Islamic State".
But it was the invasion of Iraq -- not the conflict in Syria -- that formed the "fertile spawning ground" which catapulted the previously-minor group to become a significant threat.
note: too late to edit original comment, but I meant to say "it's not the military", eg the military is being played in this global chessboard by other entities.
It seems to me that it was some group other than neocons that got us inveigled in war in Libya and Syria - thereby creating the fertile spawning ground for ISIS.